Elderly, bedridden patients, wheelchair bound patients, people with limited mobility or reduced sensation of touch, e.g. those suffering from diabetic neuropathy, have high risk of developing adverse events. Pressure ulcers, also called bed sores, are a major health issue. Bedridden patients, wheelchair bound patients, people with limited mobility or reduced sensation of touch, e.g. those suffering from diabetic peripheral neuropathy, have high risk of developing pressure ulcers. Pressure ulcers (PUs) can develop quickly and are painful for the patient. They are generally resistant to known medical therapy and, are often very difficult to heal. PUs can cause reduced anatomical or functional integrity in patients and can, occasionally lead to life threatening complications. Care for patients suffering from PUs is often time consuming, personnel intensive and expensive. Once developed, PUs increased hospital stay, imposing enormous burden on the healthcare system and diverting precious personnel resources that may be allocated for other patients. Pressure ulcers, also called bed sores, are a major health issue. Furthermore, day-to-day increased in body temperature or weight loss will increase the risk of PUs and may by a symptom of another advance event like dehydration.
Either static or long-term dynamic or punctual load, which allows pressure marks on an insensitive or passive area on the body, can lead to pressure ulcers if not taken care of in time. Such occurrences of pressure can occlude blood supply to parts of the body leading to tissue ischemia. If such pressure is not relieved over a long period of time tissue ischemia can lead to permanent cell damage causing pressure ulcers. The person with normal sensation and mobility would be immediately alerted while the person without sensation or reduced mobility—allows repeated high pressure and/or static load on the same small place on the body. This can create sores or precursors thereof.
For example, patients suffering from diabetic neuropathy have reduced sensation in their extremities and may not sense a wound or skin damage to their hands and/or feet. In such patients, a wound or skin damage on the foot can occur without detection, and the condition can lead to complications such as severe infection, slow healing wounds and risk of amputation. Therefore it becomes important for staff at the hospital or nursing home to constantly monitor vulnerable areas of the body and especially observe pressure related alteration of the skin that may be precursors of pressure ulcer.
So far, the most effective care for an at-risk patient is to relieve the pressure which, in hospitals, is commonly done by periodically repositioning bed-bound patients. Because every patient has levels of risk of occurrence of PUs depending on factors such as age, sex, disease conditions, blood pressure, nutrition, etc., some patients may need more frequent repositioning than others. Determining the schedule for repositioning is difficult may yet be unable to prevent occurrence of PUs.
Existing pressure relieving massage mattresses with inflatable chambers, where the different chambers are inflated and deflated in different intervals. The desired effect of these massage mattresses are relocation of the weight loads of the patient prolonging the time span the patient is able to be in the same position without developing a PU. These massage mattresses do not reposition the patient which is vital to avoid PU's and they increase the shear stress on the patient skin while inflating and deflating, which may also lead to develop PU's.
Devices for monitoring patients to prevent and/or detect PUs generally include an array of pressure sensors placed in close proximity to parts of a patient's body that are at a higher risk of forming PUs. The pressure sensors record pressure on the at-risk parts and provide the data to a caregiver so that the caregiver may relive the excess pressure from particular parts by suitably repositioning the patient. However, in generally, such devices are expensive and do not, by themselves, absorb or relieve pressure. For example, it would be rather expensive to change a sock having an array of pressure sensors on a daily basis. Furthermore, there may be problems with machine washing and/or autoclaving, as the connection (e.g., a cable) from the sensor to the electronics may not be adequately protected. Moreover, such devices technologies fail to utilize pressure relieving and shock absorbing areas of the patient's body that could otherwise be used. Furthermore, the dimensions of sensor array devices and spatial constraints for placing these arrays in proximity to a certain body part limit the available locations for placement of such devices. For example, while it may be suitable to use such devices on a mattress or a sheet, it may not work in a shoe or a sock because of the limited space available for placing the sensor without chaffing the user's foot.
Today the development of acquired PU is still of great concern in hospitalized health care. In the United States, PU are observed in more than 500,000 annual inpatient hospital stays. PU is a painful, incapacitating and potentially fatal complication to routine medical and nursing care. Treatment of pressure ulcers is very costly and the development of pressure ulcers can be prevented by integrating dedicated use of evidence-based best nursing practice. In the United Kingdom alone up to an estimated £2.1 billion are used annually to treat pressure ulcers—this corresponds to 4% of the National Health Service budget. In addition to the increased cost, the length of the hospital stay will be prolonged and patient recovery will be delayed as well. PU normally results from long periods with continuous pressure and shear induced to the skin and underlying soft and muscle tissue, and bony prominences. High risk patients are elderly people, stroke patients, people with diabetes, individuals with dementia, persons who use wheelchairs or are bedbound, and any patient with reduced mobility.
Often the prevention and treatment of PU are performed unsystematic and based on clinical experience of the individual health care provider. Predictive models have the potential to improve the management and prevention of PU. We have previously shown in a different medical domain how predictive models that fusing of information from different modalities could potentially help preventing serious disease. Several risk scores assessing the patient's risk of developing PU have been proposed and used in medical care such as the Braden, Waterlow and Norton scale. However, the predictive values of these risk-scales have shown low to modest accuracy and are not used in combination with sensor mattress.